A New Neuroblastoma Vaccine
Last week a new vaccine trial opened for children with neuroblastoma.
While I am yet to form an opinion on this particular option, I thought
it was certainly worthy of mention. It may very well be an interesting
option for you to discuss with your child's oncologist. But, act
quickly, this one will likely be gone fast.
The trial "A Phase 1 Study to Determine the Immunologic Effects of a MAGE- A1, MAGE- A3, NY-ESO-1 Vaccine in Patients With High Risk Neuroblastoma, Osteogenic Sarcoma, and Rhabdomyosarcoma"
is being offered at Penn State Hershey Children's Hospital. The
purpose of this phase 1 study is to determine the safety and
immunological effects of a new antibody targeted dendritic cell vaccine. The hypothesis behind the vaccine is that it could reduce the risk of relapse.
The study is in two parts. First, each patient will be screened for the presence of 3 antigens, MAGE-A1, MAGE-A3, and NY-ESO-1. These antigens can be found in fairly significant quantities on neuroblastoma, rhabdomyosarcoma, and osteogenic sarcoma cells. 70% of neuroblastoma tumors will express at least
one of these antigens. Those testing positive for one or more of these
antigens will then be consented for the treatment phase. An
individualized vaccine will be developed and administered using your
child's owndendritic cells. After about 1 month, each patient will receive a series of 3 vaccines containing 3,000,000-5,000,000 peptide pulsed dendritic cells at two week intervals. Prior to injection they will also receive Imiquimod, a topical cream, which is believed to help the immune cells travel to the tumor.
Understanding how tumor cell antigens and dendritic cell vaccines work together is a bit of a complicated subject. Essentially, dendritic cells break the antigens on the cancer cell surfaces into
smaller pieces. The dendritic cells then act as most-wanted posters for
the immune system, displaying those antigen pieces to the killer T
cells. To make a dendritic cell vaccine, scientists extract
some of the patient's dendritic cells and use immune cell stimulants to
reproduce large amounts of dendritic cells in the lab. These dendritic
cells are then exposed to antigens from the patient's cancer cells.
This combination of dendritic cells and antigens is then injected into
the patient, and the dendritic cells work to program the T cells, hopefully, forming an attack against the tumor cells.
Most important to any family of a child with neuroblastoma, however, are the questions of:
- Will it work? and
- What are the risks?
The answers to these questions are relatively unknown. Dendritic cell
vaccines hold much promise but have, thus far, shown fairly lackluster
performance in practice. However, recently there have been several
examples of these vaccines providing the immune responses that we are
looking for. There are even examples, in other cancers, of increased
survival and reduced rates of relapse using this type of strategy.
Side effects for vaccines such as this tend to be minor. Mild fever,
muscle pain and fatigue are often seen. However, as with any phase 1
trial, the true risks are unknown. Only by talking to your oncologist
or speaking with the trials primary investigator will you be able to
get a good understanding of the risks and rewards of a trial such as
this.
More information and contact information on this trial can be found here:
http://clinicaltrials.gov/ct2/show/NCT00944580